A benefit of LED (light emitting diode) lighting is a significant reduction in power use for an equivalent light output, compared to incandescent lighting. The use of LED lighting in traffic lights, however, has led to the problem of unacceptable snow and ice build-up on the lens and consequently raised potential safety concerns. The reason for the snow build up is that there may not be sufficient heat generated by the LED lighting to melt any snow and ice that may have accumulated on the lens surface. In turn, this results in a visual impairment of the traffic light signal indication.
The comparative absence of the snow build-up problem with incandescent lighting has apparently depended on the fact that incandescent lighting generates thermal energy in the form of heat which is useful in melting snow and ice from the face of the lens. Since the advent of LED lighting, there has arisen an increased number of reported incidents of obstructed signal beacons due to the accumulation of snow and ice thereon. It has been particularly observed that the build-up of snow and/or ice on prior art LED traffic lights starts at the bottom of the LED signal beacon and progressively moves upward to obstruct the traffic light.